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We model the occurrence of an environmental accident as a stochastic event, in particular the situation of an oil spill is explored. Characteristics of the ship operator, and the different types of the ship's operating environment determine a stochastic process governing the time patterns and size of spills. It is shown that both the time distribution of different types of oil spills, and the distribution of spill size are affected by pollution control instruments such as fines, by enforcement effort, and by the alert level of the operating personnel.

This paper identifies connections between the time variability of the volume of the Great Salt Lake (GSL), Utah, and selected atmospheric circulation indices. The indices considered are the Southern Os­ cillation Index (SOl), the PacificlNorth America (PNA) climatic pattern, and the Central North Pacific (CNP) index. We focus on interannual time scales. Low-frequency (interannual or interdecadal) relationships between the Great Salt Lake (GSL) volume change and atmospheric circulation indices are of importance because of their significance for the understanding and prediction of the GSL volume. We use Singular Spectral Analysis (SSA), Multichannel Singular Spectral Analysis (MSSA), and Multitaper Spectral Analysis (or Multitaper Method (MTM»), to identify persistent or nearly periodic patterns in time in each series. MSSA examines the joint modes of variability across the time series, while SSA decomposes each series into its component time patterns. MTM is used for identification of peaks and frequency band structure.

This experiment varied the time pattern of 25 tones sequences to determine its effect on subjects’ abilities to discriminate small time changes within one of two isochronous test regions. A two‐alternative forced‐choice procedure was used in which a small time change (±Δt=21, 39, or 57 ms) occurred equally often in one of the two test regions. Test regions were distinguished from surrounding context regions, where timing was variable, by higher frequency tones. Both the absolute amount of temporal variability (small, large) and the nature of temporal variability (rate‐accelerating, rate‐decelerating, and rate‐alternating) within context regions were varied. Results showed that listeners’ ability to detect time changes within test regions was poorer with large amounts of contextual variability than with smaller amounts. However, minimal effects of the patterning of tempo (rate) within context regions were found.

More than 200 Danish randomized controlled clinical trials in gastroenterology published from 1970 to 1994 were retrieved by electronic media, by hand-searching relevant journals, and by direct requests to Danish gastroenterologists. With the historical perspective through a quarter of a century, these papers are outlined to provide a survey of the pieces of information that Danish gastroenterologists have contributed to the present knowledge of therapeutics. The presented randomized controlled clinical trials constitute an impressive sum of knowledge within a diversity of topics. A cautious analysis of the time pattern for the publications in addition to the contents of the reports discloses that the discipline of planning and executing relevant controlled clinical trials is now in blossom in Danish gastroenterology.

This study investigates the relationship between macro-economic factors and the time pattern of the degree of merger activity in the U.S. economy. The results of the study imply that whether mergers are motivated by operating or financial synergy, they are closely related to macro-economic factors. The findings also indicate that this relationship is stronger for pure conglomerate than for non-conglomerate mergers, and that while the impact of the interest rate on “cash” mergers is positive, for “securities” mergers the impact is negative.

We ask how financial deregulation in Sweden during the 1980s affected housing finance by studying data on loan‐to‐value (LTV) ratios for home owners who moved recently. Accounting for the impact of demographic and economic determinants we find that LTV ratios were higher between 1985 and 1987 than in earlier and later years. This time pattern suggests that the deregulation of the mortgage institutions and the removal of the loan rate ceiling on banks in 1983 and 1984 were more important than abolishment of the bank loan ceiling in late 1985. They also indicate a decrease in loan demand and/or supply as early as 1988, i.e., well before the banking crisis.

Many studies have reported impaired selective attention in the elderly. Recent studies have isolated various underlying mechanisms of selective attention such as excitation, inhibition, and habituation. In the present study, 50 young adults and 50 elderly participants were compared on four conditions based on the Stroop Color‐Word task (neutral, habituation, Stroop and negative priming). Cross comparison of the different tasks enables examination of the various components of selective attention. The neutral condition serves as a baseline for the groups, enabling between‐groups comparison of proportional interference. The hypothesis that overall reading time of the younger group would be faster than that of the older group was confirmed. The hypothesis that the overall reading time pattern between task conditions would be neutral < habituation < Stroop < negative priming, was confirmed as well. Contrary to our prediction, negative priming caused more interference than the Stroop task for the elderly partic...

Drop-out is one of the main threats to distance education, particularly if compared with face-toface universities. However, drop-out analysis in distance education has often followed the same procedures as in face-to-face institutions. The most common drop-out definition establishes that students have abandoned the institution when they do not register for a subsequent school year; that is, the immediate rupture of the relationship with the institution is considered drop-out. However, such a approximation does not fit with the time patterns common in distance education, which involve longer term relationships and more openness to disruptures related to the students’ needs (family, work, etc.). This paper examines the long term evolution of drop-out in distance education.

Economists often try to make plausible inferences from a sizable empirical literature addressing a particular measurement, direction-of-effect, or testing issue. There are serious methodological problems associated with drawing such inferences. This article sets out some of these problems in order to make a case for their importance. After discussing these problems, the paper presents three case study examples of inference difficulties in specific literatures. It then proposes a new hypothesis about the time pattern of publication bias in empirical economics literatures. As support for this hypothesis, it presents evidence that ‘reversals in findings’ in empirical literatures in economics are not uncommon. Similarities are pointed out between the focus on inference problems in this paper, and the meta-analysis literatures in psychology and medical clinical trials.

The synonym of the best treatment method is individualization of the treatment. Based on a description of the characteristics of the patient, his or her disease, treatment volume, etc., the best method of irradiation is proposed. The individualization could be considered in terms of the individual dose distribution and individual fractionation. However, the dose distribution and the fractionation are usually treated separately. Currently the individualization of dose distribution, thanks to development of technology, is very advanced. Several methods of Intensity Modulation Radiotherapy allowed to conform the dose distribution to the actual anatomy. Dose-painting becomes a common method of treatment. Nevertheless, due to inherent characteristic of radiation used in radiotherapy, the ideal dose distribution can’t be obtained. Proton therapy does offer improved dose conformity, compared to IMRT. Another limitation in individualisation of the dose distribution is the lack of precise (description) delineation of the tumour. Several new imaging methods (positron-emission tomography and magnetic resonance) are very promising. According to Bentzen, we are able not only to conform the dose distribution to the individual anatomy but also to deliver some additional dose to tumour subvolumes with a potential resistance. To describe this type of treatment he coined a term of dose-painting by numbers. Another area for individualization is a time pattern of the dose delivery. Several randomized trials proved the importance of overall treatment time shortening to avoid rapid tumour cell proliferation. Patient-specific fractionation schedule optimization can improve the therapeutic index at least for some patients. The new imaging and molecular data and more reliable models of tumour dynamics may help in making radiotherapy more personalized.

Do long-run growth rates among the developed countries (DCs) depend on country characteristics, or is there on overall long-run growth pattern that dominates the effects of country differences? This paper empirically tests this question. The test involves regressing the pooled sample of their growth rates on dummy variables for the various countries. The test uses Maddison [1991] that provides data for annual estimates for real per capita product for 16 DCs from 1870–1989. Regressors were added for relative per capita product, the time trends of growth, and unusual time periods. The results suggest that country characteristics explain very little of the differences in growth rates. General factors, the tendency of lower per capita developed countries to grow faster, and the time patterns of growth among the DCs explain much more of the differences in growth rates.

A classic controversy in neuroscience is whether information carried by spike trains is encoded by a time averaged measure (e.g. a rate code), or by complex time patterns (i.e. a time code). Here we apply a tool to quantitatively analyze the neural code. We make use of an algorithm based on the calculation of the temporal structure function, which permits to distinguish what scales of a signal are dominated by a complex temporal organization or a randomly generated process. In terms of the neural code, this kind of analysis makes it possible to detect temporal scales at which a time patterns coding scheme or alternatively a rate code are present. Additionally, finding the temporal scale at which the correlation between interspike intervals fades, the length of the basic information unit of the code can be established, and hence the word length of the code can be found. We apply this algorithm to neuronal recordings obtained from the Globus Pallidus pars interna from a human patient with Parkinson's disease, and show that a time pattern coding and a rate coding scheme co-exist at different temporal scales, offering a new example of multiplexed neuronal coding.

As a consequence of the large changes of industry work during the last decades, the measurement techniques used for load assessment have undergone a corresponding development to, if possible, reveal hazardous load situations associated with modern production technology. This development has implied methods focusing localized loads on muscles, tendons and joints. Posture is one externally observable load factor of great importance. Load distribution within the body can be assessed by computerized biomechanical models. Another important approach is the registration of the electromyographic (EMG) activity. The latter technique provides information on time patterns of loads which lately have gained increasing attention.

Since the early I98os, US and EC antidumping (AD) policies have converged in their aims, outcomes and legal detail. This is revealed by close similarities in the structures and time pattern of their procedures (see Palmeter (1995) and Vermulst and Driessen (I995) on the legal aspects in the United States and the Community respectively). It was manifest during the Uruguay Round, where a US-EC coalition resisted any substantial change in the code for interpreting Article VI of GATT. Such convergence has not happened by chance: section II argues that it arises from the same basic policy choices having been made during the i980s. Sections III and IV describe and analyse the various aspects of this convergence. Finally, section V offers some conclusions about future consequences.

The mean temperatures of a thyristor-driven traction motor, while operating on a very busy railway-line, have been measured. The factors affecting the attained temperatures are the loading imposed on the motor, its electric-current input, the train's speed versus time pattern, the dwell times at the stations on route, and the driving practice. It is essential to timetable the operations of the train so as not to overload the traction motor, and thereby avoid its overheating and rapid subsequent breakdown. Design improvements are suggested.

In today's era, there exists a neck-to-neck competition between all the commercial organizations through E-Commerce to increase their sales and earn more profit. An organization can invest only on the group of products which are frequently purchased by its customers. So, it is a crucial data mining problem which can be a backbone to solve this problem for executives. This kind of problem lies under time pattern mining domain in which we have to find the association rules which occurs frequently in database. In this paper, we suggests using data mining as a technique to support sales in E-Commerce by using cyclic pattern mining for the scanning of item sets.

The purpose of this paper was to compare the effects of different data reduction procedures on the values of variables characterizing the time pattern of trapezius muscle activity during full work shifts. Surface electromyography (EMG) of the right and left upper trapezius muscles were obtained from 40 young subjects in different occupations, mainly electricians, hairdressers and students. The target EMG variables were gap frequency, muscle rest, and the number and duration of episodes with sustained muscle activity (from 0.13s to 30min as minimum duration). These variables were derived from the EMG recordings using different Root Mean Square (RMS) windows (from 0.13 to 6.38s), and discrimination levels between "activity" and "rest" (0.5%, 1% and 2% of maximal EMG). The results give basis for practical suggestions for EMG analyses of full work shifts. For most variables, a discrimination level of 0.5% EMGmax showed to be preferable. The time proportion of muscle rest and sustained muscle activity should, in general, be preferred over the corresponding frequency measures. Sustained muscle activity should be calculated using a RMS window between 1 and 3s, and preferably be stated in terms of variables describing time proportions of activity. Uninterrupted activity episodes longer than 10min proved not to be a useful variable due to limited occurrence in many work shifts.

Background Charcoal burning in a sealed room has recently emerged as the second most common suicide means in Hong Kong, causing approximately 200 deaths each year. As charcoal burning suicide victims have a unique sociodemographic profile (i.e., predominantly economically active men), they may commit suicide at specific times. However, little is known about the temporal patterns of charcoal burning suicides. Methods Suicide data from 2001 to 2008 on victims of usual working age (20–59) were obtained from the registered death files of the Census and Statistics Department of Hong Kong. A total of 1649 cases of charcoal burning suicide were analyzed using a two-step procedure, which first examined the temporal asymmetries in the incidence of suicide, and second investigated whether these asymmetries were influenced by sex and/or economic activity status. Poisson regression analyses were employed to model the monthly and daily patterns of suicide by economic activity status and sex. Results Our findings revealed pronounced monthly and daily temporal variations in the pattern of charcoal burning suicides in Hong Kong. Consistent with previous findings on overall suicide deaths, there was an overall spring peak in April, and Monday was the common high risk day for all groups. Although sex determined the pattern of variation in charcoal burning suicides, the magnitude of the variation was influenced by the economic activity status of the victims. Conclusion The traditional classification of suicide methods as either violent or nonviolent tends to elide the temporal variations of specific methods. The interaction between sex and economic activity status observed in the present study indicates that sex should be taken into consideration when investigating the influence of economic activity status on temporal variations of suicide. This finding also suggests that suicide prevention efforts should be both time- and subgroup-specific.

Background Although treatment adherence is a major challenge in sub-Saharan Africa, it is still unknown which longitudinal patterns of adherence are the most detrimental to long-term virological response to non-nucleoside reverse transcriptase inhibitor (NNRTI) regimens. This analysis aimed to study the influence of different time patterns of adherence on virological failure after 24 months of treatment in Cameroon. Methods Antiretroviral therapy (ART) adherence data were collected using face-to-face questionnaires administered at months 1, 3, 6, 12, 18 and 24. Virological failure was defined as viral load >40 copies/ml at month 18 and/or 24. Two combined indicators of early adherence (months 1, 3 and 6) and adherence during the maintenance phase (months 12, 18 and 24) were designed to classify patients as always adherent during the early or maintenance phase, non-adherent at least once and having interrupted ART for >2 days at least once at any visit during either of these two phases. Results Virological failure occurred in 107 (42%) of the 254 patients included in the analysis. In the early and maintenance phases, 84% and 76%, respectively, were always adherent, 5% and 5% were non-adherent and 11% and 20% experienced ≥1 treatment interruption. Early non-adherence was independently associated with virological failure (adjusted OR 7.2 [95% CI 1.5, 34.6]), while only treatment interruptions had a significant impact on virological failure during the maintenance phase (adjusted OR 2.1 [95% CI 1.1, 4.4]). Conclusions ART NNRTI-regimens used in sub-Saharan Africa seem to ‘forgive’ deviations from good adherence during the maintenance phase. Optimizing adherence in the early months of treatment remains crucial, especially in a setting of poor health care infrastructure and resources.

Background There is concern about a possible association between influenza A(H1N1)pdm09 vaccination and narcolepsy. In this study, we assessed the incidence and incidence rate of narcolepsy in the South Korean population before and after the implementation of an A(H1N1)pdm09 vaccination campaign to see if vaccination led to a change in the occurrence of narcolepsy. Methods We conducted an ecological study, comparing incident cases and incidence rates for newly diagnosed narcolepsy case-patients in South Korea, between July 2006 and June 2011. We used data from the Health Insurance Review Agency and Korea Centers for Disease Control and Prevention, which have limited information on case ascertainment. During vaccination campaign period, South Korea used non-adjuvanted and MF59-adjuvanted A(H1N1)pdm09 vaccines. Results Generally, incidence rate was highest in prepandemic period. No trend toward increase in the incidence of narcolepsy after pandemic period was found. Observation of incidence by season did not suggest any time pattern for occurrence of narcolepsy. Conclusion No increase in cases or incidence rate for narcolepsy during the A(H1N1)pdm09 vaccination campaign was found in South Korea. Our data do not support the use of MF59-adjuvanted or non-adjuvanted A(H1N1)pdm09 vaccine as a trigger for narcolepsy on a population level.

In USN system, data streams are generated from several sensor nodes continuously. Therefore, patterns from data streams can be occur continuously and be a very long sequence pattern. However, it is very expensive to mine a very long sequence pattern using existing pattern mining methods. In this paper, we define the Pattern Map to store serial patterns and we propose the Pattern Map mining to discover useful information from the Pattern Map in real-time. Also, we define the Meaning Window to produce transactions from data streams and we define the HAPM(HAsh based Pattern Map) as a new data structure to represent the Pattern Map. Finally, we introduce Local Rules and the Global Rules as a new rule concept for USN application environments.

When children are of a certain age, family life is strongly linked to the school. Because attending school is mandatory in all countries, school time imposes limits on family life and family vacations. On the one hand, school time makes other family activities impossible at that time; on the other hand, it frees parents from having to care for or supervise their children. And, in most countries, school time extends from early morning to late afternoon. Only some countries such as Austria, Germany, Greece, and, in part, Italy, Portugal, and Switzerland have historically chosen shorter school times (Allemann-Ghionda 2005, pp. 77–78). Up to 2003, elementary and secondary school traditionally ended at lunchtime for the majority of students in Germany. But German school time has become a new issue during the last 10 years, because the policy on school time has changed through the implementation and expansion of so-called all-day schools providing lunch and an enlarged and changing time pattern (including extracurricular activities) in the afternoon. Two of the reasons for increasing the number of hours students (can) spend in school each day were the poor results of German students in international assessments of education standards and the demand for a better work–life balance for parents through all-day schools. As one can expect, such moves to change some aspects of society’s self-conception have raised a lot of discussions.

We investigate human error dynamics in sequential two-alternative choice tasks. When subjects repeatedly discriminate between two stimuli, their error rates and mean reaction times (RTs) systematically depend on prior sequences of stimuli. We analyze these sequential effects on RTs, separating error and correct responses, and identify a sequential RT tradeoff: a sequence of stimuli which yields a relatively fast RT on error trials will produce a relatively slow RT on correct trials and vice versa. We reanalyze previous data and acquire and analyze new data in a choice task with stimulus sequences generated by a first-order Markov process having unequal probabilities of repetitions and alternations. We then show that relationships among these stimulus sequences and the corresponding RTs for correct trials, error trials, and averaged over all trials are significantly influenced by the probability of alternations; these relationships have not been captured by previous models. Finally, we show that simple, sequential updates to the initial condition and thresholds of a pure drift diffusion model can account for the trends in RT for correct and error trials. Our results suggest that error-based parameter adjustments are critical to modeling sequential effects.

International audience; The purpose of this study was to compare Daphnia magna responses to cadmium between two toxicity experiments performed in static and flow-through conditions. As a consequence of how water was renewed, the two experiments were characterised by two different exposure time patterns for daphnids, time-varying and constant, respectively. Basing on survival, growth and reproduction, we addressed the questions of organism development and sensitivity to cadmium. Classical analysis methods are not designed to deal with the time dimension and therefore not suitable to compare effects of different exposure time patterns. We used instead a dynamic modelling framework taking all timepoints and the time course of exposure into account, making comparable the results obtained from our two experiments. This modelling framework enabled us to detect an improvement of organism development in flow-through conditions compared to static ones and infer similar sensitivity to cadmium for both exposure time patterns. (C) 2011 Elsevier Inc. All rights reserved.

Electric vehicles are usually perceived by policy makers and the general public as an attractive means to reduce greenhouse gas emissions. In this paper we provide a rigorous assessment of the emissions resulting from the diffusion of electric vehicles. We make use of EMOB, a comprehensive model that provides a forecast and evaluation of alternative fuel vehicles diffusion in Germany in the next decades. As far as computation of emissions is concerned, our method differs from existing one by a 'pivotal marginal' or 'hourly marginal' emission computation that takes into account the predicted long-term time pattern of EV reloading. We obtain non-tailpipe emissions of around 75 g/km in 2020. Additionally, our findings cast serious doubts on the general claim that electric cars could be fed in with renewable energy in general, and with fluctuating excess supply of renewables (wind, solar) in particular.

Human capital theory predicts pecuniary returns to regional migration, but also positive self-selection of migrants. Therefore, when estimating the causal effect of migration one has to take care of potential self-selection. Several authors recommend using fixed effects models thereby controlling for time constant unobserved heterogeneity. However, if selection operates not only on wage level but also on wage growth conventional fixed effects models are also biased. In this paper we want to investigate, whether migrants are self-selected on wage growth and if this biases conventional fixed effects estimates of the returns to migration. We use data from the SOEP 1984 – 2010. First we analyze the time pattern of the wage differential between migrants and stayers to see whether they are on different wage trajectories. Second we introduce a fixed effects model with individual slopes to investigate whether conventional results are biased. JEL Classification: C33, J61, R23

This paper examines the influence that unexpected inflation has on the reported time pattern in housing returns. Two alternative models of expected inflation are used to study its effect: a rational expectations model and an adaptive expectations model. Findings indicate that both estimates of unexpected inflation are positively correlated with excess returns to housing. If inflation expectations are assumed to have been adaptive during the 1970s and early 1980s, serial correlation in the excess returns is shown to be greatly diminished when adjusted to control for unexpected inflation. However, substantial inertia in the pattern of the adjusted return series remains.

In June and July 1992 parent‐infant interactions were analyzed among the inhabitants of Tauwema (Trobriand Islands), who represent a traditionally living society. Parent‐infant interactions were continuously registered over a period of 7 days in 4 families with infants of 1,2,5, and 11 months of age using a microefectronic actometer. Based on self‐demand feeding, a remarkable synchronization between infant's and mother's movements occurred during both day and night. Despite the fact that the father also slept near the baby in the night no father‐infant correlation was found. Among the children aged 5 and 11 months no nocturnal response of both parents’ and siblings’ movements relative to infant's activity was found. Power spectra revealed inter‐individual differences of the rhythmicity patterns of infants and mothers depending on the infant's age. E.g. there is a dominant ultradian frequency of about 8 hours in the activity of the 2‐month baby, in the 5‐month‐old infant the circadian frequency pr...

A map based algorithm for tracking a pre-defined arbitrary path across a surface with a known pattern but with an unknown, variable, degree of distortion is described. The approach is intended for use with a line-scan camera receiving data line-by-line from a moving web which is continuously patterned. The intended application is in separating ribbons of textile lace by laser cutting. Emphasis is placed on minimising data manipulation to enable control information to be derived in real-time. Tests are described which investigate the robustness of the approach when used with noisy signals and web patterns which are geometrically distorted from their nominal form, laterally and/or longitudinally, by up to ±10%. A practical real-time implementation of the algorithm using DSP hardware is described.

Publication of security analysts' recommendations in the column “Inside Wall Street,” which is published in Business Week, induces abnormal returns on the publication day and the following day. The abnormal returns are robust to the use of alternative samples and methodologies. The publication increases trading volumes for the securities that are recommended to be purchased, but not for securities that are recommended to be sold. The abnormal returns and trading volumes support the view that stock prices do not adjust instantaneously when new information arrives, and that the time pattern of price adjustment depends on the time pattern of the accessibility of the information. The authors find no statistically significant difference between the average abnormal returns that are induced by recommendations that appear at the beginnings of “Inside Wall Street” columns (and are covered more extensively than others) and the average abnormal returns induced by other recommendations.

The general sense that we suffer from a `lack of time' seems to be indicative of modern culture. It also seems that, rather paradoxically, this lack of time is actually being offset by an increase in the time at our disposal: witness recent increases in leisure time (that is, time not spent in paid employment). This paper proposes to examine the contradictory effects of this development and to discuss the types of experiences which become possible once one has time to spare, i.e.: contingent experiences. There are two main questions to be considered here. First, is the perception of modern time patterns gender-specific? Second, do these different perceptions cause `time collisions' in gender relations?

The main Didymella ascospore season in Derby is June-September. 10 day running means for the years 1986–1988 have been compared with 10 day running means of rainfall and maximum temperatures. The high temperatures reached in 1987 together with substantial rainfall were very favourable for Didymella ascospore release. Diurnal periodicity showed that the expected night time pattern was only occasionally disturbed by day time rainfall. Didymella ascospore liberation is greatly increased when both temperature and rainfall are high. Temperatures of about 20° in the period before rainfall appear to greatly increase the numbers of Didymella ascospores liberated. Air has been sampled for fungal spores in Derby for many years and there is evidence of an upward trend in the June-September seasonal mean concentrations of Didymella ascospores since 1985 with no corresponding trend apparent in the corresponding June-September rainfall totals. Seasonal mean concentrations for 1985, 1987, 1988 and 1992 were at ...

A year-long study of the noise environment in the city of Kuopio, Finland was made to assess noise sources in an urban community in different seasons. A total of 7581 h of continuous noise data was collected. L eq,1 h , and L max and L AE for the noise events were measured with the aid of a computer. The noise sources for 18000 intrusive events were identified using tape recordings. This information was used to investigate the time patterns of the noise levels during different seasons and to study the importance of different noise sources. A large proportion of intrusive noise events in Kuopio did not have traffic sources and there were differences in noise levels and intrusive noise sources in different seasons.

Noise robustness of tuneable photo-refractive (TPR) filters, which can be implemented for real time pattern recognition, is assessed and compared with phase-only and classical matched spatial filters. The bandpass selectivity of the TPR filters results in sharp correlation peaks even when the input scene signal-to-noise ratio is decreased significantly.

We develop a measure of public information flow to financial markets and use it to document the patterns of information arrival, with an emphasis on the intraday flows. The measure is the number of news releases by Reuter's News Service per unit of time. We find that public information arrival is nonconstant, displaying seasonalities and distinct intraday patterns. Next we relate our measure of public information to aggregate measures of intraday market activity. Our results suggest a positive, moderate relationship between public information and trading volume, but an insignificant relationship with price volatility. THE LINK BETWEEN INFORMATION and changes in asset prices is central to financial economics. A fundamental tenet of market efficiency is that investors react to new information as it arrives, resulting in price changes that reflect investors' expectations of risk and return. Recent studies in market microstructure explore how price-volume relations are formed in financial markets, with an emphasis on intraday trading. A distinction is often made in the literature between public and private information (French and Roll (1986)). Whereas public information is available to the whole market and hence does not require trading to impact prices, private information is available to a narrow segment of the market and affects prices only through trading. Recent contributions (e.g., Admati and Pfleiderer (1988)) argue that private information plays a dominant role in explaining the time patterns of trading volume and return volatility in securities markets. Public information is relegated to a lesser role, that of an unspecified, exogenous factor. Our purpose is to investigate the rate of public information flow to see whether identifiable patterns exist that shed light on market volume and volatility relationships. We begin by describing the timing and pattern of public information arrival to financial markets. Our database consists of news stories sent via the North American wire by Reuter's News Service in a recent test year, May 1990 through April 1991. We define the rate of public information flow as the number of stories carried over the news wire per unit of time and document the rate of public information flow over various time segments, such as when

Research in cognitive neuroscience and spatial presence suggests that human mental self-localization is tied to one place at a given point in time. In this study, we examined whether it is possible to feel localized at two distinct places at the same time. Participants (N = 30) were exposed to a virtual rollercoaster and they continuously judged to what extent they felt present in the immediate environment and in the mediated environment, respectively. The results show that participants distributed their self-localization to both environments, and the two values added up to closely 100% over time. In addition, even though the judgments are highly idiosyncratic, they were almost perfectly inversely related. This indicates that individuals can distribute their self over two distinct places. These findings provide important insights about understanding of the human self-localization.

There are regional and periodic droughts in Chongqing, which impacted seriously on agricultural production and people's lives. This study attempted to monitor the drought in Chongqing with complex terrain using MODIS data. First, we analyzed and compared three remote sensing methods for drought monitoring (time series of vegetation index, temperature vegetation dryness index (TVDI), and vegetation supply water index (VSWI)) for the severe drought in 2006. Then we developed a remote sensing based drought monitoring model for Chongqing by combining soil moisture data and meteorological data. The results showed that the three remote sensing based drought monitoring models performed well in detecting the occurrence of drought in Chongqing on a certain extent. However, Time Series of Vegetation Index has stronger sensitivity in time pattern but weaker in spatial pattern; although TVDI and VSWI can reflect inverse the whole process of severe drought in 2006 summer from drought occurred - increased - relieved - increased again - complete remission in spatial domain, but TVDI requires the situation of extreme drought and extreme moist both exist in study area which it is more difficult in Chongqing; VSWI is simple and practicable, which the correlation coefficient between VSWI and soil moisture data reaches significant levels. In summary, VSWI is the best model for summer drought monitoring in Chongqing.

Movement misclassifications often occur during real-time pattern recognition control. Majority vote and a decision-based velocity ramp are two different post-processing methods that have been suggested to improve real-time control. With majority vote, spurious misclassifications are removed at the expense of an additional controller delay. With a decision-based velocity ramp, the effect of misclassifications is minimized by attenuating movement speed following a change in decision from the classifier. The goal of the study was to determine which, if any, post-processing method improved real-time control above a baseline condition that did not involve post-processing. Five non-amputee subjects controlled a virtual prosthesis in real time using pattern recognition. While performing a challenging target achievement test in a virtual environment, subjects had significantly higher completion rates (p0.04) and more direct paths to the target (p0.02) while using the velocity ramp than while using majority vote or the control condition. There were no significant differences in completion rate or path efficiency between the majority vote conditions and the control condition (p0.6). The benefits of removing misclassifications through majority vote may be offset by the added controller delay. These results highlight the need for real-time performance measures, as methods that have been shown to reduce errors during offline analysis may not improve real-time control.

Real-time pattern recognition control is frequently affected by misclassifications. This study investigated the use of a decision-based velocity ramp that attenuated movement speed after a change in classifier decision. The goal was to improve prosthesis positioning by minimizing the effect of unintended movements. Non-amputee and amputee subjects controlled a prosthesis in real-time using pattern recognition. While performing a target achievement test in a virtual environment, subjects had a significantly higher completion rate (p < 0.05) and a more direct path (p < 0.05) to the target with the velocity ramp than without it. Using a physical prosthesis, subjects stacked a greater average number of 1” cubes (p < 0.05) in three minutes with the velocity ramp than without it (76% more blocks for non-amputees; 89% more blocks for amputees). Real-time control using the velocity ramp also showed significant performance improvements above using majority vote. Eighty-three percent of subjects preferred to control the prosthesis using the velocity ramp. These results suggest that using a decision-based velocity ramp with pattern recognition may improve user performance. Since the velocity ramp is a post-processing step, it has the potential to be used with a variety of classifiers for many applications.

Procurement of major equipment plays significant roles to construction project. Suppliers use buffer time to response the uncertainty of duration in construction projects, while this pattern inevitably creates time wastage. This paper examines the buffer time pattern and finds out the origin of time wastage. Reschedule the procurement of major equipment in construction projects and create an enhanced pattern, which integrates contract, information and organization measures, to improve construction supply chain management and reduce time wastage.

If AB, and BC, it follows logically that AC. The process of reaching that conclusion is called transitive inference (TI). Several mechanisms have been offered to explain transitive performance. Scanning models claim that the list is scanned from the ends of the list inward until a match is found. Positional discrimination models claim that positional uncertainty accounts for accuracy and reaction time patterns. In Experiment 1, we trained rhesus monkeys (Macaca mulatta) and humans (Homo sapiens) on adjacent pairs (e.g., AB, BC, CD, DE, EF) and tested them with previously untrained nonadjacent pairs (e.g., BD). In Experiment 2, we trained a second list and tested with nonadjacent pairs selected between lists (e.g., B from List 1, D from List 2). We then introduced associative competition between adjacent items in Experiment 3 by training 2 items per position (e.g., B₁C₁, B₂C₂) before testing with untrained nonadjacent items. In all 3 experiments, humans and monkeys showed distance effects in which accuracy increased, and reaction time decreased, as the distance between items in each pair increased (e.g., BD vs. BE). In Experiment 4, we trained adjacent pairs with separate 9- and 5-item lists. We then tested with nonadjacent pairs selected between lists to determine whether list items were chosen according to their absolute position (e.g., D, 5-item listE, 9-item list), or their relative position (e.g., D, 5-item listE, 9-item list). Both monkeys' and humans' choices were most consistent with a relative positional organization.

We examine the extent to which hospital technologies are associated with growth in U.S. hospital costs. We create an index capturing the availability of a range of technologies in 2214 hospitals and track over the period 1996-2007, along with financial information from Medicare Cost Reports. We find that our measures of technology availability are positively correlated with hospital costs, consistent with the view that technology is an important driver of costs. However, we find that even controlling for a large number of technologies leaves a significant portion of the growth in U.S. hospital costs unexplained. While this may at least in part reflect effects of technology not captured by our measures, it suggests that the drivers of hospital cost growth go significantly beyond commonly conceptualized measures of technological change. Finally, we identify innovations that are cost increasing or cost-saving, and the time pattern of these effects.

Public and private pensions represent the main income source of Europeans in their old age. Pension provisions depend on workers’ career: workers retiring under the same pension regime might receive very different pension benefits depending on the time pattern of employment and unemployment spells, on the magnitude and the timing of income shocks and, more generally, on the age-profile of earnings (Boeri and Brugiavini 2009). Individuals are often induced to retire early, but inadequate contributions due to a short work history may reduce household’s welfare later in life (Angelini et al. 2009). Previous work has shown great variability in the patterns of transition from work to retirement (Peracchi and Welch 1994; Brugiavini and Peracchi 2005; Brugiavini et al.

Expanded hours of access and the reduction of peak system loads are often cited as advantages of remote access to online public access catalogs (OPACs). This argument is based on the assumption that remote users search OPACs when libraries are closed or when there is low internal use. The author tested this assumption by performing a transaction log analysis of the remote and internal use of the OPAC of the Research Libraries of the New York Public Library. The analysis showed that patterns of remote and internal use differed greatly. A large part of remote searching occurred when the Research Libraries were closed. Compared to internal searching, remote searching was distributed more evenly over the course of the day and the week

The linear-quadratic (LQ) model is useful in the radiobiological assessment of a wide variety of radiotherapy treatment techniques, not being confined to analysis of fractionated treatments alone. The model uses parameters that must be separately specified for tumours and dose-limiting normal tissues, and may therefore be used to help identify treatments that are most likely to maximise tumour cell kill while minimising the risk of severe normal-tissue damage. Additionally, the model is capable of making tentative allowance for the tumour repopulation that can occur during extended treatments. Intercomparisons between different types of treatment are made through the concept of the Extrapolated Response Dose (ERD). The ERD is calculated for each critical tissue and takes account of both the radiobiological parameters and the dose/time pattern of radiation delivery. Known tolerance doses for specified organs may be expressed as an ERDtolerance value, and, if a proposed 'new' treatment is to be successful, its associated ERD value must not exceed ERDtolerance. Examples of this procedure are given in this paper. It is particularly important that medical physicists fully appreciate the scope and limitations of LQ equations, as the analysis of radiobiology problems using the model often requires a degree of mathematical understanding that clinicians may not possess.

The “gambler's fallacy” is the belief that the probability of an event is lowered when that event has recently occurred, even though the probability of the event is objectively known to be independent from one trial to the next. This paper provides evidence on the time pattern of lottery participation to see whether actual behavior is consistent with this fallacy. Using data from the Maryland daily numbers game, we find a clear and consistent tendency for the amount of money bet on a particular number to fall sharply immediately after it is drawn, and then gradually to recover to its former level over the course of several months. This pattern is consistent with the hypothesis that lottery players are in fact subject to the gambler's fallacy.

We study the family of steady shapes which arise when a magnetic liquid droplet is confined in a rotating Hele-Shaw cell and subjected to an azimuthal magnetic field. Two different scenarios are considered: first, the magnetic fluid is assumed to be a Newtonian ferrofluid, and then it is taken as a viscoelastic magnetorheological fluid. The influence of the distinct material properties of the fluids on the ultimate morphology of the emerging stationary patterns is investigated by using a vortex-sheet formalism. Some of these exact steady structures are similar to the advanced time patterns obtained by existing time-evolving numerical simulations of the problem. A weakly nonlinear approach is employed to examine this fact and to gain analytical insight about relevant aspects related to the stability of such exact stationary solutions.